Physical Sciences and Mathematics Commons^™

Transformations Of Differential Equations And Applications, Despina Andrea Stavri

Masters Theses

The Sturm-Liouville problems introduced by Jacques Charles Francois Sturm and Joseph Liouville in the 19^thcentury are very important in applied mathematics. Singular Sturm-Liouville problems and two physical problems are discussed. The two physical problems are solved using two methods: Exact and asymptotic solutions. Also, the Sturm-Liouville problem's are classified using the Weyl-Kodaira Theorem. A general transformation of a third order differential equation is introduced. Oscillation and non-oscillation theorems on an infinite interval for a third order differential equation are stated. New versions of these theorems are introduced for the special cases and examples are given to illustrate them. …

Testing Heterolocalism: An Assessment Of Latino Settlement Patterns In The Southeastern United States, Kristian Dennis

Masters Theses

Previous theories of immigrant integration indicate that spatial propinquity is a necessary ingredient for a cohesive ethnic community. Wilbur Zelinsky’s heterolocalism theory suggests this is no longer the case in today’s world where technology has drastically reduced the friction of distance in human interaction. This thesis uses a mixture of quantitative and qualitative techniques to test heterolocalism’s applicability to emergent Latino communities in the Southeastern United States. The results of this research generally support Zelinsky’s theory that a growing number of ethnic communities are socially but not spatially cohesive.

Examining Regression Analysis Beyond The Mean Of The Distribution Using Quantile Regression: A Case Study Of Modeling The Internal Bond Of Medium Density Fiberboard Using Multiple Linear Regression And Quantile Regression With An Example Of Reliability Methods Using R Software, Leslie Brooke Shaffer

Masters Theses

The thesis examines the causality of the central tendency of the Internal Bond (IB) of Medium Density Fiberboard (MDF) with predictor variables from the MDF manufacturing process. Multiple linear regression (MLR) models are developed using a best model criterion for all possible subsets of IB for four MDF thickness products reported in inches, e.g., 0.750”, 0.625”, 0.6875”, and 0.500”. Quantile Regression (QR) models of the median IB are also developed.

The adjusted coefficient of determination (R² _a) of the MLR models range from 72% with 53 degrees of freedom to 81% with 42 degrees of freedom, respectively. The …

Characterizing Episodic Stream Acidity During Stormflow In The Great Smoky Mountains National Park, Edwin Bradley Deyton

Masters Theses

Episodic stream acidification occurs as storm events temporarily reduce acid neutralizing capacity (ANC) and pH. Stream acidification is suspected to have damaging effects on the health of aquatic ecosystems and biota. The objectives of this research are to 1) characterize stream baseflow and stormflow chemistries in three watersheds in the Great Smoky Mountains National Park (GRSM), 2) understand potential mechanisms responsible for episodic acidification, and 3) understand the relationship between storm event magnitude, antecedent soil moisture condition, and the stream’s pH response. Three remote, forested, high-elevation streams (Middle Prong, Ramsey Prong, and Eagle Rocks Prong) were selected in the Middle …

Factors Influencing Persistence Of Fecal Bacteroides In Stream Water, Alyssa K. Bell

Masters Theses

Fecal contamination leads to increased risk of exposure to enteric pathogens in aquatic environments used for drinking water, recreation, and commercial shellfishing. Current indicators of fecal contamination recommended by the EPA such as E. coli and enterococcus can fall short of meeting ideal indicator criteria by having widely-varying persistence in the environment, reproducing in the environment, occurring in the gut in low and variable concentrations, and requiring time-consuming assays. Furthermore, both these indicators lack the degree of host specificity needed for use in identifying sources of fecal contamination, which is an important tool for identifying and reducing fecal inputs to …

Tectonics Of The Northeastern Inner Piedmont, Northwestern Nc, From Detailed Geologic Mapping, Geochronologic, Geochemical, And Petrologic Studies With Structural Analyses Of Ductile Fault Zones, Matthew Patrick Gatewood

Masters Theses

New field and laboratory data collected for the northeastern Inner Piedmont (IP) reveal the structure and composition of a portion of the southern Appalachian crystalline core, delimited the timing of orogenesis, and provide new insight into the nature of deep crustal processes during orogenesis. Previously recognized lithologies are continuous throughout the study area and comprise two distinct crystalline thrust sheets: the Marion and Brindle Creek thrust sheets, or eastern Tugaloo and western Cat Square terranes, respectively. Western IP Precambrian- Cambrian(?) metasedimentary lithologies and Ordovician metaigneous lithologies make up the Marion thrust sheet northwest of a Neoacadian suture, the Brindle Creek …

An Applied Statistical Reliability Analysis Of The Modulus Of Elasticity And The Modulus Of Rupture For Wood-Plastic Composites, Diane Goodman Perhac

Masters Theses

Wood-plastic composites (WPC) are materials comprised of wood fiber within a thermoplastic matrix and are a growing and important source of alternative wood products in the forest products industry. WPC is gaining market share in the building industry because of durability/maintenance advantages of WPC over traditional wood products and because of the removal of chromated copper arsenate (CCA) pressuretreated wood from the market. The reliability methods outlined in this thesis can be used to improve the quality of WPC and lower manufacturing costs by reducing raw material inputs and minimizing WPC waste. Statistical methods are described for analyzing both tensile …

Reliability Analysis Of Oriented Strand Board’S Strength With A Simulation Study Of The Median Censored Method For Estimating Of Lower Percentile Strength, Yang Wang

Masters Theses

Oriented Strand Board (OSB), an engineered wood product, has gained increased market acceptance as a construction material. Because of its growing market, the product’s manufacturing and performance have become the focus of much research. Internal Bond (IB) and Parallel and Perpendicular Elasticity Indices (EI), are important strength metrics of OSB and are analyzed in this thesis using statistical reliability methods. The data for this thesis consists of 529 destructive tests of OSB panels. They were tested from July 2005 to January 2006. These OSB panels came from a modern OSB manufacture in the Southeastern United States with the wood furnish …

Laboratory Precipitation And Geochemical Investigation Of Unstable Caco3 Polymorphs: Implications For The Origin Of Precambrian “Molar-Tooth” Microspar, Emily Elizabeth Goodman

Masters Theses

Molar-tooth (MT) microspar is a volumetrically significant, globally distributed carbonate fabric that occurs almost exclusively in Mesoproterozoic and early Neoproterozoic shallow marine successions. It occurs as uniform, equant crystals, averaging 9 –15 μm in diameter (Figure 1), that characteristically fill MT structures—interconnected networks of spheroidal, spindle, and ribbon-shaped voids that formed within unlithified sediment in shallow, subtidal environments. Cathodoluminescence (CL) analysis of MT microspar reveals two chemically distinct phases: a dully luminescent spheroidal core enclosed by a luminescent, polygonal rim. Crystal size distribution analysis of MT microspar indicates spontaneous nucleation, rapid growth and varying degrees of recrystallization by Ostwald ripening, …

Process Mass Spectrometric Parameterization Of Butene Isomer Mixtures, Eloise Marie Joyce

Masters Theses

Process mass spectrometry was used for the simultaneous quantitation of hydrocarbon mixtures with either six or four components. The four component hydrocarbon mixture contains isomers to increase the complexity of the mixture spectrum. The differences in relative intensities of pure component electron ionization mass spectra provided a basis for quantitation. Quantitation accuracy and precision were found to decrease as the spectral similarities among the components increased.

Selection of which ions to monitor (parameterization) was critical to optimize the analysis accuracy, precision, and speed for all mixtures tested. An empirical parameterization algorithm based on comparison of pure reference spectra of mixture …

Measuring The Value Of Air Quality: Application Of The Spatial-Hedonic Model, Seung Gyu Kim

Masters Theses

The value of air quality improvement following the 1990 Clean Air Act Amendments is estimated at the county level in the lower 48 United States. This study applies a hedonic model to assess the economic benefits of air quality improvement using an instrumental variable approach that combines geographically weighted and spatial autoregression methods to account for spatial heterogeneity and spatial autocorrelation. Positive amenity values of improved air quality are found in five major clusters of areas across Eastern Kentucky and most of Georgia around Southern Appalachian area, the State of Illinois, on the border of Oklahoma and Kansas, on the …

Fast Determination Of Human Insulin And Its Deamidation Product By Electrospray Ionization Mass Spectrometry, Teerapat Rojsajjakul

Masters Theses

Application of the electrospray ionization (ESI) technique in mass spectrometry (MS) has played an important role in analysis of biological molecules and polymers. The focus of this thesis is to assess and extend the application of this technique in the rapid determination of human insulin and its deamidation product.

Quantitative assessment of deamidation of human insulin generally invokes relatively slow chromatographic analysis. Faster cost-effective analysis using mass spectrometry with a low-resolution analyzer is challenging because the deamidation product is only one Dalton heavier than the 5808-Da protein; low-level contamination has only a small effect on the isotope envelope. Exploiting the …

A Study Of The Homology Of Subset Spaces And Their Connection To The K-Sat Problem In Computer Science, Oliver J. Thistlethwaite

Masters Theses

It is the purpose of this thesis to introduce an idea for studying questions of computer science via topology. We begin by describing the homology of a certain space constructed from a given subset of the power set of any finite set. We then discuss how this relates to the k-SAT problem in computer science.

We shall use computers as a tool to calculate the homology groups as well as the Euler characteristic of some of these spaces. Due to the sheer number of calcu- lations needed, doing the necessary computations by hand is both impractical and impossible.

In addition, …

Transport Critical Currents In Ybacuo-Based Coated Conductors: Angular, Magnetic Field, And Temperature Dependencies, Samuel M. Travaglini

Masters Theses

High-temperature superconductivity has been a focus of much study over the past 20 years, particularly within the cuprate class of superconductors. The effectiveness of these cuprate superconductors is limited by factors including the formation of vortices within the superconductor, orientation within external magnetic fields, the strength of these magnetic fields, temperature, and whether any doping agents have been used. Any of these factors individually can affect the transport critical current levels. In this research, YBaCuO and NdBaCuO-based coated conductors were studied in a liquid-nitrogen-cooled environment at either 77 K or 65 K. Field levels were varied between 0 T and …

A Comparison Of The Deck Group And The Fundamental Group On Uniform Spaces Obtained By Gluing, Raymond David Phillippi

Doctoral Dissertations

We de…ne a uniformity on a glued space under uniformly continuous attachment maps. If the component spaces are uniform coverable then the resulting glued space is uniform coverable. We consider examples including the glued uniformity on a …nite dimensional CW complex which is shown to be uniformly coverable. For one dimensional CWcomplexes, the resulting deck group is equivalent to the fundamental group. Other properties of the deck group are explored.

Spectroscopic Investigations Of Complex Transition Metal Oxides, Jinbo Cao

Doctoral Dissertations

In this dissertation, I present spectroscopic studies of several model electronic and magnetic materials. Compounds of interest include VOx nanoscrolls, VOHPO4¢ 1 2H2O, and (La0:4Pr0:6)1:2Sr1:8Mn2O7. These materials are attractive systems for the investigation of optical gap tuning, lattice and charge dynamics, spin-lattice-charge coupling, and hydrogen bonding effects. I measured the optical properties of VOx nano- scrolls and the ion-exchanged derivatives to investigate the lattice and charge degrees of freedom. Selected V-O-V stretching modes sharpen and redshift with increasing amine size, which are microscopic manifestations of strain. We observed bound carrier localization in the metal exchanged nanoscrolls, indicating they are weakly …

Golden-Winged Warbler (Vermivora Chrysoptera) Demographics And Habitat Use And The Potential Effects Of Land Use Change On Golden-Winged And Cerulean Warblers (Dendroica Cerulea) In The Cumberland Mountains Of Tennessee, Lesley Penfield Bulluck

Doctoral Dissertations

The golden-winged warbler (Vermivora chrysoptera) is an early successional Nearctic-Neotropical migrant songbird undergoing population declines range-wide. The Cumberland Mountains contain one of the southernmost populations where goldenwingeds occur in relatively high densities on old reclaimed surface mines. The three objectives of this research were to (1) describe the basic demography and habitat use of this population, (2) compare the demography of the Cumberland population to a population in Ontario, and (3) to model alternative land use scenarios and the impacts on both the golden-winged warbler and the cerulean warbler (Dendroica cerulean), another declining Nearctic-Neotropical migrant that …

Remote Sensing Of Impact Crater-Exposed Subsurface Lithologies And Martian Rayed Crater Systems, Livio Leonardo Tornabene

Doctoral Dissertations

Impact cratering is ubiquitous, energetic and fundamental geologic process acting on the solid planetary bodies. As a consequence, craters provide planetary scientists with useful information regarding the surface and subsurface properties of planetary bodies. Specific mineral and lithologic compositions can be ascertained via craters in two ways: 1) by the remote sensing of crater-exposed subsurface materials, or 2) by studying the differentiated meteorites (e.g., lunar, Martian, etc.) ejected from their surfaces by highenergy impacts under specific conditions. As a proof of concept for subsurface-crater mapping, remote sensing techniques were applied to a terrestrial impact structure. Visible-near infrared (VNIR), short-wavelength infrared …

Beauveria Bassiana, A Cotton Endophyte With Biocontrol Activity Against Seedling Disease, Mary Ruth Griffin

Doctoral Dissertations

Beauveria bassiana isolate 11-98 is entomopathogenic, endophytic in tomato, and has biocontrol activity against Rhizoctonia solani on tomato. The objectives of this study were to determine 1) if B. bassiana is endophytic in cotton, following seed treatment; 2) if B. bassiana can protect cotton against seedling pathogens; 3) if different conidial rates, applied to seed, alter effectiveness of B. bassiana; and 4) mechanisms of biocontrol used by B. bassiana against plant pathogens. Cotton ‘Delta Pine 436’ seed was inoculated with isolate 11-98 conidia, sown in a gnotobiotic system, and then isolated from surfacesterilized seedlings on selective medium. Using scanning …

Design And Synthesis Of Novel Sultams: A Family Of Non-Nucleoside Reverse Transcriptase Inhibitors And Modeling Studies Of A Rhodium Catalyst, Riyam Kafri

Doctoral Dissertations

3-Phenyl-2,3-dihydro-1,2-benzisothiazole 1,1 dioxide (NSC108406), identified as an HIV-1 reverse transcriptase inhibitor, is chosen for lead optimization. A series of analogues are docked using SYBYL FlexiDock into both wild-type (wt) reverse transcriptase (RT) and Tyr181 --> Cys181 (Y181C) RT, from the dataset of efavirenz (Sustiva®) bound to the enzyme. Minimizations using genetic algorithms are performed, and the lowest energy conformations are evaluated. Five structures emerge as good fits either in both enzymes or only in Y181C RT. 3-(m-Cyclopropylphenyl)- and 3-(isopropylfuranyl)-2-methyl-2,3- dihydro-1,2-benzisothiazole 1,1-dioxides do not exhibit improved binding in wt RT over efavirenz. In the Y181C pocket, the furanyl ring …

Ecological Indicator Development, Integration And Knowledge Mapping, Aaron Dean Peacock

Doctoral Dissertations

The overall goals of this project were: (1) to develop a microbiological ecological indicator that would describe military land disturbance, (2) integrate previously collected ecological indicator data from five separate research teams, and (3) produce knowledge maps with the resulting information that illustrates how the selected indicators are involved in ecosystem processes. To address goal one, soil samples were obtained from four levels of military traffic (reference, light, moderate, and heavy) with an additional set of samples taken from previously damaged areas. Using the soil microbial biomass and community composition as ecological indicators, reproducible changes showed increasing traffic disturbance decreases …

Preparation, Characterization And Reactivities Of Early Transition Metal Silyl Compounds, He Qiu

Doctoral Dissertations

This dissertation focuses on syntheses, characterization and reactivities of Groups 4 and 5 metal amide silyl complexes free of anionic π-ligands.

A summary of the research in this dissertation is provided in Chapter 1. Chapter 2 reports an unusual reaction between Ta(NMe₂)₄SiBu^tPh₂ (1) and O₂. Three products (Me₂N)₄Ta(OSiBu^tPh₂) (2), (Me₂N)₃Ta(ONMe₂)(OSiBu^tPh₂) (3) and (Me₂N)₂(Ph₂Bu^tSiO)₂(Me₂NCH₂NMe)₂Ta₂(μ …

Static And Dynamic Magnetism In The Electron-Doped High-Temperature Superconductor Pr0.88Lace0.12Cuo4-Δ And In The F-Electron, Non-Fermi Liquid Alloy Sc1-XUXPd3, Stephen Dennis Wilson

Doctoral Dissertations

Here we present detailed studies of the spin dynamics within the electron-doped high temperature superconductor Pr_.88LaCe_.12CuO_4-δ (PLCCO) and within the non-Fermi liquid metal Sc_1-xU_xPd₃ (ScUPd). Comprehensive neutron scattering experiments were carried out mapping the evolution of magnetism within these systems as they are tuned across their respective phase diagrams. The novel features of the magnetic spectra within these systems are correlated with known anomalies in their quasiparticle behaviors driven through either the appearance of a superconducting phase in PLCCO or the emergence of a non-Fermi liquid phase in ScUPd.

For …

Innovative Methods Of Biomedical Molecular Analysis: Capillary Electrophoretic Study Of Amyloid Beta Conformations And Magnetically Assisted Transport Evanescent Field Fluoro-Assays, Amber D. Wellman

Doctoral Dissertations

Though the study of the human proteome (proteomics) is far more complicated than that of the genome, it may prove to be the next step toward gaining insight into the operation of biological systems. Understanding the role proteins and peptides play in disease, whether that be by their structure, expression or function, could lead to the identification of disease biomarkers for diagnosis or engender possibilities for treatment. To this end, the work discussed herein delves into the capillary electrophoretic (CE) analysis of amyloid beta conformations involved in abnormal aggregation and the creation and optimization of a novel bioassay method. By …

Structure And Transport Properties Of Epitaxial Oxide Thin Films: From Synthesis To Characterization, Junsoo Shin

Doctoral Dissertations

Epitaxial thin films and heterostructures based on perovskite oxides have attracted significant attention in physics since perovskites exhibit an enormous range of electrical, magnetic, and optical properties, making them exciting systems for studies of the fundamental physical mechanisms of interactions between electron, lattice, and spin degrees of freedom. This dissertation has been focused on ferroelectricity in lowdimensional ferroelectric materials using ultra-thin ferroelectric epitaxial films (BaTiO₃) with a metallic electrode (SrRuO₃) by studying polarized ordering of the crystal structure and electronic transport through the films. High quality and highly oxidized epitaxial films are a prerequisite for the …

Evaluation Of Forest Management To Improve Breeding Habitat For Songbirds In Oak-Hickory Forests At Tennessee National Wildlife Refuge, Benjamin Stephen Thatcher

Doctoral Dissertations

Partners in Flight (PIF) recommends using silviculture to improve breeding habitat conditions for migrant landbirds. Alternative thinning treatments may benefit priority landbird species by increasing structural complexity in second-growth forests. However, the effects of thinning on landbird populations in oak (Quercus spp.)-hickory (Carya spp.) forests have not been experimentally demonstrated. I used a randomized and replicated large-scale manipulative experiment to evaluate the effects of thinning (i.e., crown-release and gap creation) on forest habitat characteristics and avian populations at the Tennessee National Wildlife Refuge. I collected data during 2001 (pre-treatment) and from 2002 to 2005 (1 to 4 years …

Automated Gene Classification Using Nonnegative Matrix Factorization On Biomedical Literature, Kevin Erich Heinrich

Doctoral Dissertations

Understanding functional gene relationships is a challenging problem for biological applications. High-throughput technologies such as DNA microarrays have inundated biologists with a wealth of information, however, processing that information remains problematic. To help with this problem, researchers have begun applying text mining techniques to the biological literature. This work extends previous work based on Latent Semantic Indexing (LSI) by examining Nonnegative Matrix Factorization (NMF). Whereas LSI incorporates the singular value decomposition (SVD) to approximate data in a dense, mixed-sign space, NMF produces a parts-based factorization that is directly interpretable. This space can, in theory, be used to augment existing ontologies …

Leaf: A Learning-Based Fault Diagnostic System For Multi-Robot Teams, Balajee Kannan

Doctoral Dissertations

The failure-prone complex operating environment of a standard multi-robot application dictates some amount of fault-tolerance to be incorporated into every system. In fact, the quality of the incorporated fault-tolerance has a direct impact on the overall performance of the system. Despite the extensive work being done in the field of multi-robot systems, there does not exist a general methodology for fault diagnosis and recovery. The objective of this research, in part, is to provide an adaptive approach that enables the robot team to autonomously detect and compensate for the wide variety of faults that could be experienced. The key feature …

Synthesis And Characterization Of Atomically Dispersed, Vanadosilicate Catalysts In Si8o20-Based Building Block Solids, Ming-Yung Lee

Doctoral Dissertations

Silica supported vanadium complexes have attracted interest as catalysts for a variety of catalytic reactions in the past two decades. Although many strategies have been developed for incorporating vanadyl species on silica surfaces, controlling dispersion and loading while simultaneously producing single site catalysts remains a challenging goal in this context and in catalysis as well.

A simple strategy for producing single-site and site-isolated vanadyl species has been explored which allows for control of both the connectivity to the support as well as the local surface structure around a V=O group. The main elements of this strategy involve construction of the …

Analysis Of A Gluonic Penguin Decay With The Babar Detector, Gerald Conrad Ragghianti Jr.

Masters Theses

This thesis presents a branching fraction analysis of the neutral B meson decay channel B → ϕK⁰_s where the K⁰_s decays to π⁰π⁰. The decay is dominated by gluonic penguin transitions, which have been very important for the main program of BABAR: the search for physics beyond the Standard Model. The decay channel has been established and is included in the CP analysis, which is sensitive to new physics. The data set consists of 227 million BB̅ pairs recorded by the BABAR detector at the Stanford Linear Accelerator Center. Sophisticated analysis techniques …